Papermaking machine



June 1940' w. H. MILLSPAUGH 2,204,426

urn-amuse mcams Filed June 19, 1956 I s Sheets-Sheet 1 INVENTOR I B! l m MW 'h ATTORNEY JuneTl, 1940- w. H. MILLSPAUGH 2,204,426

7 rAPERmAxIus nmcams Filed June 19, 1956 a Sheets-Sheet 2 INVENTOR i I BY I '1 ATTORNEY WrH. MILLSPAUGH PAPERIAKING MACHINE Filed June 19, 1936 3 Shee'ts-Sheet 5 INVENTOR- .WM M

A'ITORNEY Patented June-11, 1940 rarnnmxme mom William Hulse Millsnaugh, Sandusky, Ohio, as-

signor to Sandusky Foundry and Machine 00., Sandusky, Ohio, a corporation of Ohio Application June 19,1936, Serial No. 86,167 In Great Britain June 21, 1935 2 Claims. (CI. 92-49) This invention relates to papermaking machines of the kind in which, as in a Fourdrinier machine and in a vacuum-forming cylinder ma-' chine, an endless making wire travels forwardly from the paper forming portion of the machine over and under a couch roll, or over a couch roll and over and under a turning or driven roll spaced from and in advance of the couch roll, and then returns to the paper formingportion of the machine, and a wet sheet of paper carried by the upper portion of the making wire, is, after being partly dewatered while on the making wire, transferred automatically and continuously by vacuum or suction action from the upper side of a portion of the making wire in advance of a vertical plane passing through the axis of the couch roll, to an endless press felt by which it is delivered to press rolls arranged beyond the couch roll and spaced therefrom and one at least 0 ofwhich is a suction roll by means of which the wet sheet of paper is further dewatered.

A papermaking machine of the kind referred to is described and shown in the specification of my former Patent 1,930,104. In that machine, the press, comprising twosuperposed suction rolls, each provided internally with lower and upper suction boxes, and a plain top roll, is arranged above a portion of the making wire extending between a couch roll and a turningor drive roll with the lower suction roll directly above and in close proximity to the said portion of the making wire, and a first press felt is arranged to travel directly above the said portion of the making wire and below the lower suction roll, so that a wet sheet of paper carried by the making wire, is automatically and continuously transferred from the making wire to the felt by the suction or vacuum action set up in the lower stationary suction box within the lower suction roll, and is carried upward and then backward through the bite between the two suction rolls and then transferred from the first felt by suction or vacuumaction set up in the lower'suction box within the upper, suction roll, to a second press felt by which it is carried through the bite between the upper suction roll and plain top roll, the wet sheet being further dewateredat each bite, the expelled water being removed by the upper suction boxes within the respective suction rolls.

With such an arrangement of the press, when it becomes necessary to replace the making wire, the turning or drive roll has to be lowered, or rolled back towards the couch roll, which usually involves the employment of expensive operating equipment and additional internal equipment. Also, the lower suction roll of the press has to be provided internally with the lower stationary suction box, which necessitates the making of such suction roll larger and more'expensive than 5 it would otherwise need to be, and theprovisionof a heavy and elaborate framing or stands for supporting the press, which interfere with the replacement of the making wire.

Furthermore, with such an arrangement of 1. press and felts it is not possible to bring the wire side of the transferred wet sheet of paper into contact with the bare top roll in order to eliminate the wire marks'in the sheet, so that the variety of papers that can be produced by the aid of such a press and felts is limited.

The present invention relates to improvements in papermaking machines of the kind referred to, and it has for its object to avoid the serious practical disadvantages above mentioned, and at the same time to enable a partly .dewatered wet sheet of paper to be transferred in a better manner than heretofore, by suction or vacuum action, from the upper side of the forward portion of the making wire of the machine, after passing over the top of the couch roll, to a press felt, and thence passed between press rolls in such a manner that it will further be dewatered andconditioned in an advantageous manner forv subsequent treatment. The conditioning of the wet sheet of paper is'efiected by reversal of the sheet in its passage'through the press, whereby paper fibres which unavoidably project from the wire side of the sheet and also filling material that has passed to the wire side of the sheet while on the 35 making wire are pressed back into the sheet.

' A papermaking machine of the kind referred to, embodying the present invention is characterised in that the press, comprising one or more suction rolls and one or more plain rolls, is arranged at a distance from and beyond the upper forward extending makingportion of the wire of the machine and the couch roll, and that there are associated with the making wire, couch conditioned. The suction transfer roll may be driven from the felt, or by variable speed driving mechanism to synchronise its speed with that of the making wire and felt.

The press can be constructed in various forms and in one or more sections, and the independent suction transfer roll and associated felt can be arranged in various positions in relation to the forward portion of the making wire, beyond the couch roll, from which a wet sheet of paper is to be transferred to the said felt. Also, the press rolls and press felt or felts can be arranged in Various ways to enable the wire side of a transferred wet sheet of paper on its passage through the press to be brought into contact with a plain press roll so that the wire marks thereon can be rolled or ironed out, and so that the sheet of paper can if desired, be smooth rolled on one or each side preparatory to subsequent treatment.

In the accompanying illustrative drawings, Figs. 1 to 9 inclusive, show in side elevation and diagrammatically and by way of example, various ways in which the invention above set forth, can

be carried into practical effect in papermaking machines of various kinds.

In the example shown in Fig. l of the drawings, l is the making wire of a papermaking machine, which may, for example be a Fourdrinier papermaking machine, or a vacuum-forming cylinder papermaking machine, the forward end of the said making wire extending over a couch roll 2 and over and around a turning roll 3, which may be a driven roll, so that a flexible length I of the making wire is suspended between the two rolls. vWhen the paperxnaking machine is a Fourdrinier papermaking machine, the couch roll 2 would be a suction couch roll, as shown. When the papermaking machine is a vacuum forming cylinder papermaking machine, the making wire i would be driven by the vacuum forming cylinder and the couch roll 2 may be a plain unperforated roll. The press comprises three superposed rolls 4, 5 and 6 bearing upon one another and arranged, as shown, at a distance from the making wire and rolls 2 and 3, to admit of the wire being readily removed from the said rolls 2 and 3 and replaced, as and when necessary, without interference by the press. The lower press roll 4 is a positively driven suction roll and is provided internally with a single stationary suction box I of known kind, arranged at its upper portion, and extending rearwardly from the inlet side of the bite between the said press roll 4 and the adjacent press roll 5. The press roll 5, which is also a suction roll and positively driven, is provided internally with upper and lower stationary suction boxes 8 and 9 respectively, of which the lower one 8 is a suction transfer box arranged at the outlet side of the bite between the rolls 4 and 5, and the upper one 9 is arranged at the inlet side of the bite between rolls 5 and G. The upper press roll 6 is a plain unperforated roll free to be rotated by the roll 5 and a felt travelling through the bite between the said rolls 5 and 6, but it also may be positively driven. I is an independent displaceable suction transfer roll provided internally at its lower portion with a non-rotatable suction box Ii and arranged over the flexible suspended portion I of the making wire I between the rolls 2 and 3. i2 is an endless press felt extending under the suction transfer roll l0 so that, when the machine is in operation, a wet sheet of paper will be transferred continuously from the portion l of the making wire. I to the lower side of the felt I! by the suction or vacuum set up. in known way,

in the suction box ll of the said suction transfer roll I. The said suction transfer roll I0 is so mounted, as for example by counterbalanced levers, that it can readily be swung or otherwise moved away from the making wire, as and when necessary, and so that when in position for use, it will bear lightly upon the said suspended portion i of the making wire through the felt l2 and the wet sheet of paper on the wire. It may be driven by the felt, or it may be positively driven, and it may be a rubber covered suction roll if desired.

In the example now being described, the press felt l2 passes upward and forwardly to and through the bite between the suction rolls 4 and 5, then backwardly through the bite between the upper suction roll and plain roll 6, and thence returns directly to and around any suitable arrangement of felt rolls, a guide roll and a stretch roll, to the suction transfer roll I0. i3 is a second endless press felt extending upwardly and forwardly with the first felt 12 through the bite between the two suction rolls 4 and 5 from which it extends directly in a forward direction. and returns around any suitable arrangement of felt rolls i4, guide roll i4 and a stretch roll l5 to the rear side of the suction roll 4 as shown. The arrangement is such that'awet sheet of paper transferred from the portion I of the making wire I to the press felt [2 by the action bf the suction box ii in the suction transfer roll III, will be confined between that felt and the second press felt l3 and passed through the first bite between the suction rolls 4 and 5, the water thereby pressed from the sheet being withdrawn by the suction box 1, which is arranged within the suction roll 4 to extend rearwardly of the said bite. The second felt l3 then leaves the pressed and partly dewatered sheet of paper, which is held against the first press felt l2 by the suction action set up in the lower suction box 8 of the suction roll 5, assisted by the pressure of the external air, and is carried by the said felt l2 backward through the upper bite between the suction roll 5 and the plain upper roll 6. The said felt l2 then leaves the further pressed and partly dewatered sheet of paper which is carried upward by the upper roll 6 and delivered in a forward direction from the top thereof, as indicated at A, and over a carrying roll I6, towards a drier drum ll. Water pressed from the sheet of paper at the second bite will be withdrawn through the upper suction box 9 of the suction roll 5 and thus removed at the inlet side of the bite. It will be seen that the position of the sheet of paper will be reversed at the second bite, so that water will be drawn first in one direction at one bite, and in the opposite direction at the second bite through the sheet of paper, and that the wire side of the sheet, which initially was at the lower side of the sheet, becomes the upper side at the secondbite where wire marks therein will be rolled or ironed out by the upper plain press roll -6 and such side thus rendered even and smooth.

In the modified construction shown in Fig. 2, the first felt I2 with the transferred wet sheet of paper on its lower side, is carried forward from the suction transfer roll l0, it may be under a turning roll l8, to the bite between the two suction rolls 4 and 5 where it is met by the second felt IS, the two felts, with the interposed wet sheet of paper, then passing through the said bite where water will be pressed from the sheet and removed by the suction box 1 arranged at the inlet side of the bite and within the suction roll 4. After passing through the bite, the sheet'of paper is transferred from the first felt I2 to the second felt II by the action of the suction trans-' fer box 8 of the suction roll 5, assisted by the pressure of the external atmosphere, the felt l2 then returning from the bite to the suction transfer roll III. The felt "with the transferred sheet of paper thereon, then passes upward around the suction roll 5 and through the bite between that roll and the plain roll 6 where it is further dewatered, the expressed water being drawn oif by the suction box 9 arranged within the roll 5 at the inlet side of the bite. The sheet of paper, indicated at A, is then delivered over a carrying roll I6 towards a drier drum II, the felt I3 leaving it and returning to the bite between the suction, rolls 4 and 5.

In the modified arrangement shown in Fig. 3, the press is divided into two sections, each comprising two superposed rolls, the first section comprising a lower suction roll I and an upper plain roll 6, and the second section comprising two plain press rolls 4 and 6". Or roll l may be a suction roll, if desired. In this arrange ment, the wet sheet of paper is transferred, as in the other arrangements, from the making wire I by the suction transfer roll III to the felt I2 which carries it onward, it may be around a turning roll I8, to and through the bite between the suction roll 4 and plain roll 6 without the aid of a second felt, the water pressed from the sheet being removed, as before, through the suction box 1 of the suction roll 4. The felt I2 then returns to the suction transfer roll I0 leaving the sheet of paper A free to be carried upward by the plain roll 6 from which it passes forward over a carrying roll I9 and passes, together with a second felt l3, through the bite between the pair of rolls 4 and 6 one of which is a driven roll. The felt I3 then leaves the sheet of paper A which passes over the carrying roll I 6 towards a drier drum II. In this arrangement the wire side of the wet sheet of paper comes in contact with the plain press roll 6 before the sheet has been previously pressed and partly dewatered by passing through a bite, which is advantageous, as the wire marks therein can be removed in a more effectual manner at this first pressing and the under or wire side is further improved by setting the fibres and filler. By afterwards passing the sheet of partly dewatered paper between the pair of rolls 4, 6 both of its sides or surfaces are smooth rolled and thus usefully conditioned for future use.

Figs. 4, 5 and 6 show arrangements similar to Figs. 1, 2 and 3 respectively, except that the turning roll 3 for the making wire is dispensed with, and the wire passes over and under'the roll 2, which may be a suction roll, as shown, or a plain roll, and is driven, and the displaceable suction transfer roll III with felt I2-is arranged to bear lightly against the upper part of such roll2 beyond the top of the roll and the adjacent portion of the making wire I, and the wet sheet of paper thereon, so as not to injure the wire. For this purpose, the said suction transfer roll I0 may be covered with rubber having holes therein registered with those in the metal shell portion of the roll, or be mounted to bear in a yielding manner against the making wire, or be carried by means that will limit its movement towards the wire so that it will not press heavily against the wire.

Fig. 7 shows another arrangement in which the press is divided into two sections. The first section comprises a lower suction roll I having therein lower and upper suction boxes'l and 1 respectively though the lower one I' may in some cases be omitted, and a plain top roll 6, and the second section comprises a lower suction roll I having therein lower and upper suction boxes I and 9" respectively, and a plain top roll 8", the lower suction box 8' of the suction roll 5" being adapted to act as a suction transferbox. The displaceable suction transfer roll it is arranged to bear, through the felt I2 and wet sheet of paper, against the suspended portion I of the making wire extending over rolls 2 and 3, and the felt I2, to which a wet sheet of paper is automatically transferred by the said roll III, as before, is led forward under the suction roll 8 of the firstsection and through the bite between that roll and its associated plain roll 6 and then upward against the lower side of the suction roll 5 of the second section, adjacent to the suction transfer box 8 therein, where it is met by a second felt I3 and where the pressed and partly dewatered sheet of paper is transferred from the first felt I2 to the second felt I3 by the suction or vacuum set up in the said suction transfer box 8. The felt l2 then leaves the sheet of paper and returns to the suction transfer roll I0, leav ing the sheet of paper to be carried upward by the felt I3 and forward through the bite between the suction roll 5 and plain roll 6", the felt I3 carrying the further pressed and dewatered sheet of paper onward for a distance, as indicated, and then leaving it free to be moved onward, it

may be between smoothing rolls, not shown,

the wire marks therein will be rolled 0r ironed out and surface fibres set, and the position of the sheet of paper will be reversed at the second bite, so that the opposite side of the sheet will be smoothed by the plain roll 6: Also, water will be pressed from the sheet of paper by the press roll 6 and removed by the suction. box I of the suction roll 8 and also by the press roll 6 and removed by suction box 9 of the suction roll 5'.

Fig. 8 shows a similar arrangement to that shown in Fig. 7 except that the turning roll 3 for the making wire I is omitted and the suction transfer roll I0 is arranged to bear, with its felt l2, lightly against the upper part of the roll 2 through the making wire I and wet sheet of paper thereon. The roll 2 may be a driven suction couch roll.

The arrangements shown in Figs. 1 and 4, in

which a wet sheet of paper is held between two felts I2 and I3 when passing through the first bite between the suction rolls land 5, are specially suitable for use in a papermaking machine for making thin paper, such as tissue paper.

The arrangements shown in Figs. 3, 6, 7 and 8 are suitable for making fine paper requiring both sides of the paper to be smooth finished.

The arrangements shown in Figs. 2, 5, 7 and 8 are suitable for fast running papermaking machines.

When it is desired to apply markings, such as water marking, to the sheet of paper, this may advantageously be done by a marking roll applied to the sheet after it has passed through the first bite only of the press, as shown at M in Fig. 6, as very distinct markings can then be through the second bite of the press and is therefore less wet. as shown at M in Figs. 1 and 4,

- when markings are not desired to be shown so prominently.

It is necessary that the making wire I and endless felt I! should travel at the same speed or a constant relative speed in order that a wet sheet of paper can be transferred continuously and regularly, that is to say without breaking. from the making wire to the felt by suction action 'of the section transfer roll "I. For this purpose, the turning roll, or couch roll, each of which is driven, and moves the making wire forward, and the lower driven suction press roll 4 which moves the first felt forward, should be caused to rotate at the same peripheral speed, or at a constant relative speed. Arrangements of variable speed or speed synchronising mechanism suitable for attaining this result are known. Suitable arrangements of such mechanism are described in the specification of another application No. 86,168 filed by me on June 19, 1936.

The suction press rolls have usually been made of bronze and uncoveredgto present hard surfaces to the felt. When however the press comprises two-superposed suction rolls 4 and 5 and a plain top roll 6, as in the examples hereinbefore described with reference to Figs. 1, 2, 4 and 5, the middle or upper suction roll 5 may be provided, as shown in Fig. 9, with a rubber covering 20 the outer portion at least of which is of yielding density, the said covering being formed with a large number of radial holes in register with those in the metal shell portion of the roll. The use of a rubber covering on the suction roll 5 is of special advantage, as it has the effectof providing, with the lower suction roll 4 and upper plain roll 6, two elastic or yielding bites between the three rolls by the use of only one rubber covered working roll.. -The lowersuction roll 4 may also be provided with a rubber covering similar to that on the upper suction roll 5 but this will usually be unnecessary.

The rubber covering 20 on the upper suction roll 5 can be ground from time to time, as and when it is necessary to renew its working surface. When -this is done, its diameter will of course be reduced from time to time. In order that the two suction rolls 4 and 5 shall rotate at all times at the same peripheral speed it will be necessary to provide in connection with the said rolls, variable speed or synchronising mechanism, indicated at 2| and 22 (Fig. 9) of any known or suitable kind. One construction of such mechanism, of the epicyclic type, suitable for the purpose, is described in the specification of another application No. 86,169 for Letters Patent filed by meon June 19, 1936.

It will be seen that in each of the arrangements hereinbefore described, the opposite sides of the sheet of paper will be reversed in position in passing through the press or presses, and that the wire side of the sheet will, except in the arrangements shown in Figs. 2 and 5, come in contact with a plain press roll, either at the first bite, or at the second bite, between the press rolls, for rolling or ironing out wire marks therefrom.

a What I claim is:

1. A papermaking machine of the character described comprising a making wire, a transfer felt engaging said wire and a suction transfer roll arranged over a run of said felt for transferring a fibrous web from an end portion of the making wire to the lower side of said felt, and a suction press independent of said suction transfer roll and located at a distance forwardly from the making wire and from said suction transfer roll and receiving said transfer felt and web, said suction press comprising a lower hard surfaced suction roll having an upper suction box for downward withdrawal of water from the felt and the web, a cooperating upper suction roll arranged within said felt and having a lower suction box and having therein a second suction box at the top thereof for downward withdrawal of water from the felt and the web, and a smooth surfaced pressure roll cooperating with the top of said upper suction roll and directly engaging the wire side of the web, said upper suction roll of the suction press having a yielding rubber covering adapted for yielding engagement with the hard surface of the upper smooth surfaced pressure roll and the lower hard surfaced suction roll of the press, and a press felt extending partly around at least one of the suction rolls of the suction press and cooperating with said transfer felt to carry the web therebetween through the first bite of the suction press.

2. A papermaking machine of the character described comprising a making wire, a transfer felt engaging said wire and a suction transfer roll arranged over a run of said felt for transferring a fibrous web from an end portion of the making wire to the lower side of said felt, and a suction press independent of said suction transfer roll and located at a distance forwardly from the making wire and receiving said transfer felt and web, a press felt extending partly around at least one of the suction rolls of the suction press and cooperating with said transfer felt to carry the web therebetween through the first bite of the suction press, said suction press comprising a lower suction roll having an upper suction box for downward withdrawal of water from the felts and the web, a cooperating upper suction roll having a lower suction box and having therein a second suction box at the top thereof for downward withdrawal of water from the transfer felt and the web, and a smooth surfaced pressure roll cooperating with the top of said upper suction roll and directly engaging the wire side of the web.

WILLIAM HULSE MILLSPAUGH. 

